Hi Hiro,
I think you are trying to hard to find significance in the word 'strike'. 'To strike a deal' is just a standard phrase that has evolved.
I interpret striking in 'strike a deal' as referring more to decisiveness and finality than to actual hitting.
You might like to also consider a phrase like 'When I met her, she struck me as an intelligent person'. The meaning here is that this was the immediate, quick impression I received. She didn't actually hit me.![Smile [:)]](/emoticons/emotion-1.gif)
Best wishes, Clive